The invention relates to a vessel electrode line for a cardiac pacemaker.
In the therapy of different chronic cardiac irregularities, implanted cardiac pacemakers have long been used in connection with stimulation electrodes disposed on an intracardiac electrode catheter and positioned on the inner wall of the heart; these electrodes stimulate the excitable heart tissue, thereby compensating for a defect in the endogenous cardiac impulse formation and conduction system.
The design of the electrode lines has been repeatedly improved. With the objective of long-term assurance of a good contact between the stimulation electrode(s) and the heart tissue, and in the interest of an energy-saving, reliable stimulation, numerous technical solutions have been found for anchoring the electrode lines to the heart wall, both in the ventricle as well as in the atrium, and fundamental, practical improvements have been made successfully.
Electrode lines, especially for implantable defibrillators, have also been proposed; these lines are inserted into large vessels near the heart, and impart the defibrillation energy to the vessel wall.
EP 0 601 338 A1 describes such an electrode system for an implanted defibrillator, having at least two intravascular coil electrodes (spiral-shaped electrodes) that are held in place by virtue of their size, and have no special anchoring means. One of these large-surface defibrillation electrodes can be disposed in the vena cava superior, while a further one can be disposed in the coronary sinus.
U.S. Pat. No. 5,571,159 describes a temporary catheter for atrial defibrillation, which has, in addition to a first, spiral-shaped electrode section positioned in the atrium, a second electrode section, which is positioned in the pulmonary artery, as well as an inflatable balloon at the distal end for positioning the electrodes.
EP 0 566 652 B2 describes an electrode configuration that is designed in the manner of a stent and can be expanded by a dilation balloon; it is used as a defibrillation electrode in a blood vessel, especially in the coronary sinus.
For special applications, such as so-called bi-atrial or multi-site stimulation, it can be useful to position pacemaker stimulation or sensing electrodes in a vessel near the heart, particularly in the coronary sinus, because an electrode implantation in the left atrium is particularly problematic. The known, large-surface defibrillation electrodes are fundamentally unsuitable for this purpose.